Can elevating platform assemblies have been used for decades in beverage filling machinery. These can elevating platform assemblies comprise a piston rod extending from a cylinder to which a can platform is non-rotatably mounted using two countersunk screws. Ordinarily, an apertured platform wear plate is superimposed contiguously over the platform and the countersunk screws pass through countersunk apertures in the wear plate as well. A stirrup shoe or contoured centering guide is superimposed upon the top of the wear plate (or platform, if no wear plate is used) against which successive cans are rapidly displaced during the filling process, just prior to upward displacement of the piston rod.
The beverage filling equipment described above was designed for and worked well with metal cans having a relatively broad bottom base or footprint. However, the beverage industry, to save on the quantity of metal, including aluminum, used per can, has progressively reduced the size of the footprint of the can. Through a series of reductions, the diameter of the footprint has gone from 2.600 inches in a size 211 can to 1.875 inches in a size 202 can, which are currently being used.
Accordingly, the inherent stability of the can during the filling process has been reduced, especially in lightweight aluminum cans and the ease with which the stability of this smaller footprint can is disrupted has greatly increased. As a consequence, the smaller footprint can, using the older can platform assembly, has been found to de-stabilize as and after as it is shifted across and onto the top apertured surface, as the case may be, resulting in significant damage to the can, filler seal, and packaged cans, frequently requiring significant down time for the beverage filling machinery. The can tends to rock as and after it crosses the top apertured surface. Also, when engaging the standard stirrup, the smaller footprint can, especially when formed of lightweight material, tends to tip. Thus, the can may be cocked or misaligned as it enters the fill valve, which can cut the sealing gasket causing machinery and production line down time.
It is possible under these conditions to bend or knock down the flange of the can. This situation in turn can cause a mismatch with the lid during the seaming process, causing a leaker, which may be detected as a low fill, or it may get into the finished goods in the warehouse causing expensive damage by leaking at that point. These situations can result in a non-seal between the can and the valve or can sealing gasket during the filling process, resulting in low or non-fill can coming off the filler. This in turn, can cause jam-ups on the transfer or in the can seamer during the seaming process, due to their light weight and because of the speed these machines run. Again, causing expensive production line down time, to clear the down cans on the transfer or clear out the cans jammed in the seamer.
At the discharge, if the can does not get a nice smooth transfer and is shaken or rocked, it can result in a low fill can, resulting from spillage, or it can cause foaming between the filler and seamer on the transfer, again resulting in a low filled can. Both situations are expensive in lost product, cans, lids, and production line down time.